48 MHz Cortex-M0 with USB and CAN in a 4x4 mm package
The STM32F042G6U6: It packs 32 KB of Flash and 6 KB of SRAM, with a peripheral set that includes USB, CANbus, I²C, SPI, and multiple UARTs — all in a 28-pin UFQFPN package measuring 4x4 mm.
Memory budget and peripheral fit
With 32 KB of program Flash and 6 KB of RAM, this MCU targets control applications with moderate firmware — motor commutation, sensor fusion, USB dongle firmware, or CAN gateway logic. The USB peripheral with dedicated 48 MHz oscillator support simplifies full-speed device implementation, and the CAN interface connects directly to automotive or industrial bus networks.
For layouts, stitch vias under the pad to the ground plane — without them, thermal resistance climbs and the junction temperature limits continuous operation above 70°C ambient. The 24 I/O pins include 5 V-tolerant inputs, so level shifting is not needed for legacy 5 V logic interfaces.